Concrete M350: basic characteristics and application

Concrete M350 - an excellent structural material, which allows to produce very responsible designs for different purposes and various prefabricated elements. After its solidification, this composition is characterized by high resistance to external influences, has good characteristics, especially compressive strength. In modern construction it is concrete class B25 that is the leader both in popularity and sales.

Application of the material

Concrete M350 class B25 is used in almost all types of construction. From it, floor slabs, monolithic foundations, walls, crossbars, columns, reinforced concrete structures and other structural elements of residential, industrial and administrative structures bearing high loads are made of it. Also from this mortar make road airfield slabs, operated in conditions of maximum loads.

Let us examine in detail the characteristics that this building material possesses.

Characteristics

Let us consider the strength index of a set for compression. Measured in MPa, it is determined by class B25 (1 m3 of material without breaking integrity is capable of withstanding a pressure of 25 MPa). Increased strength B25 is achieved due to the presence of a mixture of more cement. In addition to strength, this brand of cement has other, equally important indicators: frost resistance, mobility and water resistance.

Mobility

This indicator varies in the values from P2 to P4. But the level of strength can be increased to large values, if the concrete is supplemented with special additives - plasticizers.

Water Resistance

Concrete B25 has a water permeability index - W8. This parameter indicates that the material is capable of not passing moisture through itself, even if it acts on it under considerable pressure. Thanks to this, the grade of M350 concrete can be used in areas with a high groundwater table.

Frost resistance

The frost resistance index F200 indicates that this material will not lose its properties and structural integrity after two hundred freezing and thawing cycles. Such concrete can be used in harsh climatic conditions.

Volume weight

This figure in concrete M350 is 1800-2500 kg / m³. However, most often the bulk density (density) of this material varies from 2200 to 2400 kg / m³.

Main Components

Concrete M350, as a rule, is produced as a mixture of cement, water, sand and solid filler, such as gravel crushed stone or granite. To improve the properties of this material, admixtures and plasticizers are added to its composition, so that the scope of this concrete grade is expanded

For the manufacture of a solution of class B25 use:

• cement;
• sand;
• Crushed stone;
• Water;
• Plasticizers;
• Antifreeze additives.

It should be noted that the components used for the preparation of the solution may differ in their characteristics and parameters, namely the particle size, strength, purity, and moisture.

For example, as the filler can serve:

• Sand of fine-grained, coarse or medium fraction;
• Gravel (lime or granite);
• Rubble and screenings.

It is also worth noting that concrete B25 has an increased percentage of cement, which contributes to a fairly rapid solidification.

Proportions

To prepare 1 m ^{3 of} this material you will need:

• 400 kg of cement M400 or M500;
• 752 kg of sand, free from impurities;
• 175 liters of water;
• 1 ton of solid filler (for example, crushed stone).

In order to obtain high-quality and durable concrete M350, it is important not only to strictly observe the composition proportions for 1 m ³ , but also to thoroughly mix all the components so that the resulting mass is homogeneous. A poorly mixed composition significantly reduces the strength of this material.

Preparation of the solution

• First, add dry ingredients (cement and sand) to the concrete mixer and mix thoroughly.
• Add water. At the same stage, a plasticizer or other additive is added to the solution.
• Added in water rubble or gravel.
• The solution is thoroughly mixed.

Concrete M350: price

Manufacturers themselves set the price for the material by summing up all the costs, the bulk of which falls on crushed stone and cement. To make a profit, a trade mark-up is made in excess of the cost price. That is why each manufacturer has a "own" final cost, which largely depends on the cost of raw materials.

Each developer himself chooses who to buy concrete M350. The average cost of this material with gravel filler without delivery will be from 3,000 rubles. For 1 cubic meter of the mixture, with granite rubble - from 3,700 rubles.

If antifreeze additives are introduced , the price will start from 4,000 rubles. Also, the cost of concrete is affected by its watertightness - than this figure is higher, the price is more expensive. So, we can conclude that the cost of the material depends on the manufacturer and the cost of purchasing components.